1. Field of the Invention
This invention relates to a virtual prosthetic limb system that can be used to design and evaluate new prosthetic limbs, serve as a platform for control algorithm design and sensor/signal selection, and train patients to use a given prosthetic limb.
2. Discussion of Related Art
Many individuals in the United States today are living with upper extremity amputations. These amputations most frequently result from trauma and affect young persons, especially for the soldiers wounded in Afghanistan or Iraq. A robotic arm with a fully functioning hand will significantly improve the quality of life for these amputees. Designing a robotic prosthetic arm with an optimal control mechanism that matches an individual's needs with minimum training time requires a lot of time, effort and money. A virtual prosthetic limb system that can simulate any possible design of prosthetic limb in a realistic way will significantly reduce the time, effort and money in developing a new robotic prosthetic limb, will reduce the actual training time for amputees to use the real prosthetic limbs and provide a platform for experimentation with any of a variety of possible control methods. Some research has been reported on creation of a virtual prosthetic arm system. In one such project, Orsborn, et al, (Orsborn, Amy et al, “Simulation of an Above-Elbow Myoelectric Prosthetic Arm for Development of an Implanted Myoelectric Control System”, (http://www.phys.cwru.edu/undergrad/Senior%20Projects/SeniorProjectPosters/AmyOrsbornPOSTER.pdf)), developed a basic prosthetic model and the framework required for a multi-component simulator using myoelectric signals. In another related project reported by J. Burck, M. J. Zeher, R. Armiger and J. D. Beaty, entitled “Developing the World's Most Advanced Prosthetic Arm Using Model-Based Design”, and published by The Math Works in News & Notes, in 2009, they developed a Virtual Integration Environment (VIE) that included a limb simulation environment, constructed using MathWorks tools and Model-Based Design. The VIE allowed users to control the virtual prosthetic arm with different control inputs, e.g., switches or joysticks.
To develop a more advanced virtual prosthetic limb system, the present inventors adopted advanced technologies to, among other things (i) simulate the interactions between and among the virtual prosthetic limb and virtual objects; and (ii) to build a more realistic visualization system; and (iii) to “connect” the virtual prosthetic limb and the residual limb of a patient in two directions, namely, to change the position of the virtual prosthetic limb according to the movement of the residual arm of a patient, and to provide feedback to the patient according to the events in the virtual space. The inventive virtual prosthetic limb system can be used for designing and evaluating new prosthetic arms, as a platform for control algorithm design and sensor/signal selection, patient training, and recording limb movements and control signals during clinical investigations for performance analysis. For example, as a design platform it could be used in studying how to connect a robotic prosthetic arm into the nervous system and/or into the brain (see for example the publications “Extraction algorithms for cortical control of arm prosthetics” by Schwartz, A B, Taylor, D M, Tillery, S I, Curr. Opin. Neurobiol. 11, 701-707 (2001); “Cortical control of a prosthetic arm for self-feeding” by Velliste M, Perel S, Spalding M C, Whitford A S, Schwartz A B, Nature, Vol 453 19 Jun. 2008 doi:10.1038; and “Using virtual reality to test the feasibility of controlling an upper limb FES system directly from multiunit activity in the motor cortex” by Taylor D M, Schwartz A B, In Proceedings of the 6th Annual IFESS Conference: 2001 Jun. 16-20; Cleveland. 2001:132-134, all of which are incorporated by reference hereinto).
The inventors herein have recognized a need for a virtual prosthetic limb system that will minimize and/or eliminate one or more of the above-identified deficiencies.